Triple announcement coming this week: Sigma 50mm f/1.2, Nikon 28-400mm f/4.0-8.0 and new Sony firmware update?

There are three planed announcement this week:

• Sigma 50mm f/1.2 E and L-mount lens coming on March 26
• Unconfirmed: Sony A1 and A7sIII firmware announcement on March 27
• Nikon 28-400mm f/4.0-8.0 Z-mount lens on March 28

I actually heard there might be one more announcement btu I got no details about what exactly to expect…